The word contaminative is playable in Words With Friends™, no blanks required. Because it is longer than 7 letters, you would have to play off an existing word or do it in several moves.
Words With Friends™ Letter Score: 25
Highest Scoring Words With Friends™ Play In The Letters contaminative
:
Seven Letter Word Alert: (34 words)
aconite, amentia, anaemic, ancient, animate, anionic, aviatic, avionic, catenin, catmint, caveman, coatman, connive, contain, content, convent, imitate, invoice, mancave, meiotic, mention, miniate, minivan, mitotic, montane, nematic, nictate, nonmate, nonmeat, tetanic, titanic, titmice, vitamin, vitiate